Couldn't do CTRL because it interfered with other IDE commands, so I used CTRL + ALT, which is a little awkward on the hand, but oh well. Took me a while to get used to AHK's weird scripting language, but eventually I got it. Thanks for suggesting the program.
Here's the code if anyone else wants to use this.
^!w::send {up}
^!s::send {down}
^!a::send {left}
^!d::send {right}